His victim is a hoobae who graduated from the same middle school as him, they have a sunbae hoobae relationship
At the time of the bullying the victim was in 2nd grade middle school (a 02'er) and Yoon Minguk was a grade above, 3rd grade middle school

On Produce X, they revealed that he's a 00'er, but he's only a grade above the victim

The victim was going to the hospital to visit his friend and he met Yoom Minguk and another noona (friend). (She was the same age as Yoon Minguk)

They were throwing jokes together, the victim, YMG and the nuna
but the noona started claiming that the jokes that the victim made about her was bad and that YMG and her were "hurt" by them
+ The victim had no idea what that nuna was referring to

Then YMG told the victim to come with him to a place in the hospital
And he started abusing the age system and treated him like f*cking sh*t
He kept saying stuff like "Since I'm in 3rd grade, I can abuse the age system"ㅋㅋㅋ

The victim had to follow him in the male's washroom

He didn't bring him in the washroom because he couldn't talk with him in the hospital hallway, rather he brought him to the washroom so he can beat him up

The victim kept apologizing to Yoon Minguk the whole time

Behind Yoon Minguk, there was other friends of his looking
The kids already knew that Yoon Minguk was to start hitting him, so they all kept telling him to stop hitting him

Yoon Minguk slapped the victim's face across the cheek and he didn't say anything and just left

The victim is still mad about it and even more mad about the fact that someone like him is going to promote in the celebrity industry

Imagine how the victim would feel if someone like Yoo Minguk debuted?
So let's just try to get rid of him on the show

There's also friends on him on FB saying how he used to drink and there's pictures of it, there's no proof of it, so I'm just going to overlook this part for now

So far, what I know is that this thing is spreading like wild fire on Twitter? People all all trying to get rid of him ㅋㅋㅋ